ds18b20: use accessible pin for DS18B20 one-wire
ds18b20: use accessible pin for DS18B20 one-wire

Standard is P1.6 except where that's unavailable; EXP430F5529LP does not
have P7.7 available.

pabigot/bsp430,pabigot/bsp430,pabigot/bsp430,pabigot/bsp430